Endorphins, as Gretchen Reynolds describes them, are “the world’s sole celebrity peptide,” and are given credit for runners’ high, that sweet sense of mild euphoria that many athletes feel after prolonged exercise. But wait. Now come spoil sport scientists with some disenfranchising news about enphorphin molecules: they’re big, really big, way too big to cross the blood brain barrier. Endorphins are out; but what’s in? Reynolds reports that scientists now think runners’ high is caused by a different neurochemical system within the body and brain, the endocannabinoid system. That assumption is supported by several research projects, including one in which researchers bred mice with no functioning endocannabinoid receptors. The scientists found that although mice usually love to run, the genetically modified animals, given free access to running wheels, ran about half as much as usual. And yes, stoney, endocannabinoids are related to cannabis. Read more about that here.
Health, fitness and lifestyle tips for people over 50 who still like to play hard
Saturday, May 31, 2025
This was expertly explained in Chris Bergland’s book “The Athlete’s Way: Sweat and the Biology of Bliss” published in 2007.